I have 4 images that I scanned and saved as TIFF using my 4 in 1 desktop scanner/printer thing.
I drew all the images myself by hand using the same pen, so the originals are quite consistent.
When I open the files in GIMP, the levels are not consistent from one image to the next. If I put them side by side, they don't look like they belong together. Some "black" lines are darker than others, and some white backgrounds have more noise. I tried adjusting the levels manually on each image and that improved the individual image quality, but there is still variation amongst the set.How can I use GIMP to (hopefully) batch adjust the levels so they are consistent with each other again?
I realise that the problem probably comes from the scanner itself, but I've looked at the settings and can't see how to fix it there, so I'm hoping to be able to fix it after the fact.